Title: Shoulder Dystocia
1Shoulder Dystocia
- Or,
- The heads out what next?
- Christian A. Chisholm, MD
- Division of Maternal-Fetal Medicine
2Objectives
- At the completion of this presentation, the
participant should be able to - Define shoulder dystocia (MK)
- Name three risk factors for shoulder dystocia
(MK, PC) - List potential complications, both maternal and
fetal, of shoulder dystocia (MK) - Describe the maneuvers used to relieve a shoulder
dystocia (MK, ICS)
3Definition
- a delivery that requires additional obstetric
maneuvers following failure of gentle downward
traction on the fetal head to effect delivery of
the shoulders. - ACOG, Practice Bulletin 40 (November 2002)
4Definition
- Prolonged head-to-body expulsion time
- Objectively defined as 60 seconds
- Deliveries with head-to-body interval of gt 60
seconds more commonly have higher birth weight,
shoulder dystocia, and low 1 minute Apgar scores - Beall et al 1998 Spong et al 1995
5Functional Definition
- A delivery in which the shoulders do not follow
the head as usual, but rather are delayed in
delivering or require the use of ancillary
obstetric maneuvers to effect delivery. - The anterior shoulder may be impacted behind the
symphysis pubis, or (less commonly) the posterior
shoulder behind the sacral promontory
6Incidence
- Reported to occur in 0.2-2 of births
- May recur with a higher frequency, but this is
really unknown - Many women and clinicians will opt for cesarean
in the future, especially if there has been a
fetal injury - Recurrence rates reported 1-17
7Risk Factors
- Maternal diabetes mellitus
- Fetal macrosomia
- Multiparity
- Post-term pregnancy
- Previous macrosomic infant
- Previous shoulder dystocia
8Macrosomia
- Birth weight in excess of a specific weight,
usually defined as either 4500 grams (1.5 of
births) or 4000 grams (10 of births) - Birth weight gt 4500 grams rate of shoulder
dystocia is 10-25 - Birth weight gt 4500 grams AND maternal diabetes
rate of shoulder dystocia is 20-50
9Large for gestational age
- Birth weight that exceeds the 90th centile of a
standard growth curve, regardless of gestational
age. - A baby may be LGA without being macrosomic
10Pathophysiology
- A mismatch between fetal size and maternal
pelvic capacity - Positional variations vertical rather than
oblique orientation of shoulders - Increased diameter of shoulder girdle
- Subcutaneous fat deposition may be increased in
infant of diabetic mother especially with
sub-optimal glucose control
11Anatomy of the Brachial Plexus
- Nerve roots from C5-C8 and T1
- Merge into three trunks
- Superior (C5, C6)
- Middle (C7)
- Inferior (C8, T1)
- Each splits into anterior and posterior divisions
12Anatomy of the Brachial Plexus
- The six divisions regroup into three cords
- Posterior all 3 posterior trunk divisions
(C5-T1) - Lateral anterior divisions of upper and middle
trunks (C5-C7) - Medial continuation of lower trunk (C8, T1)
13Anatomy of the Brachial Plexus
14(No Transcript)
15Anatomy of the Brachial Plexus
16Brachial Plexus Injuries
- Strain or stretch
- Partial disruption
- Complete avulsion
17Brachial Plexus Injuries
- Injury primarily to lateral trunk (C5,6, 7) leads
to Erbs palsy adducted shoulder, extended
elbow, and flexed wrist (waiters tip) - Injury primarily to the medial trunk (C8, T1)
leads to Klumpkes palsy paralyzed hand with
good shoulder and elbow function
18Maternal Complications
- Post-partum hemorrhage occurs in 11
- 4th degree laceration occurs in 3-4
19Into the Delivery Room
20Clinical Management
- Step One Recognize the presence of a shoulder
dystocia - Step Two Be sure enough help is present
- Nursing
- Obstetrics
- Pediatrics
- Anesthesiology
21Clinical Management
- Step Three Apply primary maneuvers
- Mc Roberts maneuver
- Oblique suprapubic pressure
- Step Four Apply secondary maneuvers no
prescribed order - Rubin Woods screw Posterior arm All-fours
Clavicular fracture
22Clinical Management
- Step Five (concurrent)
- Repeat steps three and four (different operator?)
- Consider if an episiotomy is needed (intentional
4th degree?) - Step Six Apply final (heroic) maneuvers
- Zavanelli symphysiotomy
23Steps One and Two
- The operator determines a shoulder dystocia is
present - Personnel needed
- Nursing
- At least two to assist with maneuvers
- One to serve as recorder, as in a code 12
situation - Pediatrics full resuscitation readiness
24Steps One and Two
- Personnel (continued)
- Anesthesiology
- Obstetrics
- Attending to supervise and step in as needed
- 2 residents at minimum
- Ideally 2 at perineum
- One to assist with maneuvers (suprapubic
pressure) away from perineum
25Step Three Primary Maneuvers
- McRoberts maneuver
- Patient positioned with hips at edge of the
broken-down birthing bed - Both hips are sharply flexed with knees remaining
flexed (knees to shoulders) - Ideally performed by staff, not family, to assure
it is adequately performed - No benefit to prophylactic McRoberts
26McRoberts Maneuver
27McRoberts Maneuver
- This maneuver assists delivery by
- Straightening maternal lumbar lordosis
- Rotates symphysis superiorly and anteriorly
- Improving angle between pelvic inlet and
direction of maximal expulsive force - Elevates anterior shoulder allowing posterior
shoulder to descend
28McRoberts Maneuver
29Oblique suprapubic pressure
- Usually applied in concert with McRoberts
maneuver - Directed downward and laterally in order to
effect rotation of the fetal anterior shoulder
under the symphysis - Should be applied from the fetal posterior
30Oblique suprapubic pressure
31Step Four Secondary Maneuvers
- There is no conclusive evidence that one maneuver
is superior to another - In each patient, the operator must decide which
maneuver will be most effective - This is a good time to decide about an episiotomy
is there room to get your hand in? - Time to initiate perinatal code (4-2012)
32Woods screw maneuver
- Apply pressure on the clavicle to effect rotation
of the shoulders out of the vertical orientation - As fetus rotates, anterior shoulder should pass
under symphysis - May be a good choice for a right-handed operator
when the fetal occiput is oriented to the
maternal right
33Woods screw maneuver
34Woods screw maneuver
- Potential complication
- Fetal clavicular fracture IN DIRECTION OF APEX OF
LUNG
35Rubins maneuver
- Apply pressure to the fetal scapula to effect
rotation of the shoulders out of the vertical
orientation - As fetus rotates, anterior shoulder should pass
under symphysis - May be a good first choice for a right-handed
operator when the fetal occiput is directed to
the maternal left
36Rubins maneuver
- May result in need for less traction and less
brachial plexus strain than McRoberts maneuver - Gurewitsch, 2005
37Delivery of Posterior Arm
- The operator inserts a hand into the vagina and
locates the posterior arm. - The operator applies pressure in the antecubital
fossa to flex the elbow across the chest - The operator grasps the forearm or hand and pulls
it out of the vagina
38Delivery of Posterior Arm
- The anterior shoulder should pass under the
symphysis - Rotation maneuvers (Woods or Rubins) can be
applied if needed - This maneuver will tend to be more difficult with
ones non-dominant hand
39Delivery of Posterior Arm
40Delivery of Posterior Arm
- Potential complications
- Fracture of humerus
- Fracture of clavicle
41Gaskin All Fours Maneuver
- Attributed to midwife Ina May Gaskin
- An option for a patient without anesthesia
- Traction is applied in the opposite direction
(still toward the floor, but now directed towards
delivery of the posterior shoulder first)
42Intentional clavicular fracture
- Apply pressure over mid-clavicle in a vector AWAY
from the lung - May be difficult to perform
- If successful, may reduce the diameter of the
shoulder girdle - Potential complication
- Lung injury
43Still not out?!
44Step Five Regroup and Repeat
- Considerations
- Time passed so far?
- Episiotomy?
- Different operator?
- Make OR preparations!
45Step Six Final Steps
- Zavanelli maneuver (cephalic replacement)
- Relax uterus with terbutaline
- Rotate head back to OA (reverse restitution)
- Flex neck
- Upward pressure
- To OR
46Step Six Final Steps
- Symphysiotomy
- Not commonly done when cesarean is available
- Last ditch effort
- Insert Foley catheter
- Use vaginal hand to laterally displace urethra to
avoid injury - Incise symphysis through mons pubis
47Do not
- Panic
- Apply any more lateral traction than would be
applied in an uncomplicated delivery - Apply fundal pressure may worsen the shoulder
impaction or even rupture the uterus - Cut a nuchal cord until after the shoulders are
released
48Do
- Remain calm
- Communicate well
- Mark time of head delivery
- Consider calling out time in one minute
increments - Call for help
- Document clearly and legibly
49Do
- Be sure to debrief as a team after the delivery
is completed - Opportunity to analyze situation and critique
team performance - Opportunity to be sure documentation is
consistent - Who did what becomes very important
- Send cord gases
50Do
- Review with the family exactly what happened and
answer questions soon after delivery, but
probably not immediately - Follow the babys course in the nursery
- Notify Risk Management
51References
- Shoulder Dystocia (Practice Bulletin 40).
American College of Obstetricians and
Gynecologists. November 2002. - Rodis, JF. Management of fetal macrosomia and
shoulder dystocia. Up to date, v 14.1 last
updated October 12, 2005. - Brachial Plexus. Wikipedia, the online
encyclopedia. http//en.wikipedia.org/wiki/Brachi
al_plexus Accessed March 21, 2006. - Beall, MH, et al. Objective definition of
shoulder dystocia a prospective evaluation. Am J
Obstet Gynecol 1998179934. - Spong CY, et al. An objective definition of
shoulder dystocia prolonged head-to-body
interval and/or the use of ancillary obstetric
maneuvers. Obstet Gynecol 199586433 - Gurewitsch ED et al. Comparing McRoberts and
Rubins maneuvers for initial management of
shoulder dystocia an objective evaluation. Am J
Obstet Gynecol 2005192153.